EP2694321B1 - System for charging an electric or hybrid vehicle - Google Patents

Description

The present invention generally relates to the safety of users of electric or hybrid vehicles whose charge is made by connection to an electrical network. More particularly, the present invention relates to electric or hybrid vehicles whose charging can be carried out in particular on a private electrical installation or home network.

In order to standardize the different charging methods of this type of vehicle, the IEC 61851-1: 2010 standard recommends a vehicle-level charging system that must communicate with the electricity distribution network via a so-called pilot line via a vehicle. an ac charging connector and imposing depending on the charging mode used, for example in the mode 3 defined in this standard a number of additional functions by means of a control circuit called "pilot circuit".

The first mode of charging, called "mode 1", defined in this draft standard corresponds to a charging of an electric or hybrid vehicle on a private electrical installation or domestic network. This mode of charging poses the particular problem of requiring a large power, for a long time and this repeatedly can lead to a risk of overheating of certain elements such as the electrical connection to the network.

Although it is known in the prior art devices to protect electrical outlets against possible overheating that can cause burns to a user handling such outlets or fires if overheating is too important, these devices are not adapted to a charging system as recommended by current standards. For example, the document DE3331847 which presents a electrical socket equipped with a bimetallic cutting circuit if the plug warms up, is not suitable for a charging system allowing charging in several modes via a pilot line. The document WO 2011/006775 A2 discloses a charging system of an electric or hybrid vehicle comprising an AC charging connector adapted to be connected to a domestic electricity distribution network via an electrical connection socket, and processing means for determining the use or not a domestic charging mode (ie a charging mode 1 as defined in IEC 61851-1: 2010). This charging system does not allow charging according to several modes via a pilot line. An object of the present invention is to meet the disadvantages of the prior art mentioned above and in particular, first of all, to provide a secure charging system for a load via a domestic electricity distribution network.

For this purpose, a first aspect of the invention concerns a charging system of an electric or hybrid vehicle comprising an AC charging connector adapted to be connected to a domestic electricity distribution network via an electrical connection socket provided with a a temperature sensitive device, and processing means for determining the use or not of a domestic charging mode, characterized in that the charging system further comprises polarization means of the temperature sensitive device, activated when a domestic charging mode is used and means for determining a value representative of the temperature of the electrical connection socket by means of the polarized temperature sensitive device. Such a charging system makes it possible to detect if the charging mode used is a domestic charging mode (ie mode 1 according to IEC 61851-1: 2010), and in this case to secure the charge by controlling the temperature of the socket electrical connection by the use of polarization means for monitoring the evolution of the temperature-sensitive device built into the socket during charging. This charging system is particularly suitable for old or outdated electrical installations and / or for the use of inappropriate extensions as it prevents overheating of the connection with the domestic electrical distribution network. In addition, such a charging system is economically viable insofar as the additional cost for its implementation is low.

According to an advantageous embodiment, the charging connector and the electrical connection socket are connected by transmission means comprising a ground wire and at least one pilot wire forming a pilot line. The use of such a pilot line makes it possible to ensure standardized communication between the distribution network and the vehicle charging system so as to allow in particular a charge of the vehicle according to mode 1 or mode 3 as defined in FIG. the IEC 61851-1: 2010 standard. According to another advantageous embodiment, there is further provided a pilot circuit connected to the pilot line to ensure the compatibility of the charging system with other charging modes that the domestic charging mode. The integration of such a pilot circuit makes it possible to comply with current standards imposing additional functions on the charging system to enable charging in different modes. For example, to comply with the IEC 61851-1: 2010 standard, the pilot circuit is able to verify the connection of the vehicle to an electricity distribution network, to continuously check the integrity of a protective connection to earth, to excite or de-energize the charging system and to select a charge rate.

According to another advantageous embodiment, the polarization means comprise a polarization source in series with a polarization resistor. The bias source will preferably be a voltage source so that the polarization of the temperature sensitive device through the bias resistor can be accomplished.

According to an advantageous variant, in which the pilot circuit comprises means for blocking the passage of the current, the polarization source is a source of negative bias activating the locking means of the pilot circuit. The use of a source of negative polarization makes it possible to avoid disturbances of the temperature measurement possibly caused by elements of the charging system, as for example the pilot circuit using the locking means of this pilot circuit.

According to another advantageous variant, the activation of the biasing means is carried out by a switch arranged on the bias circuit of the pilot line by the series connection of the source and the biasing resistor, for example in series between said source and said bias resistor. The switch is controlled by determining whether or not to use a home charging mode so as to implement polarization means only when necessary.

According to another advantageous embodiment, the means for determining a value representative of the temperature of the electrical connection socket are identical to the processing means for determining the use or not of a domestic charging mode. The reuse of the same means for two different functions makes it possible to reduce the components necessary for the charging system and thus to reduce the cost of implementation.

According to another advantageous embodiment, means for switching off the load activated when the value representative of the temperature of the determined electrical connection socket is greater than a predetermined threshold. These breaking means ensure the safety of the load and the user in case of detection of overheating at the socket by cutting the load so as to prevent overheating of the electrical connection socket that can be manipulated by hand and any fire starting because of such overheating.

According to a second aspect, the invention relates to an electric or hybrid motor vehicle comprising a charging system according to the first aspect.

According to a third aspect, the invention relates to a charging method of an electric or hybrid vehicle according to the second aspect, connected to a domestic electricity distribution network via an electrical connection socket provided with a temperature-sensitive device, characterized in that it comprises the steps of: (i) detecting the connection of the AC charging connector to a electricity distribution network; (ii) determine the use or not of a domestic charging mode; (iii) biasing the temperature sensitive device of the electrical connection socket when the charging mode used is a domestic charging mode; and (iv) determining a value representative of the temperature of the electrical connection socket by means of the polarized temperature sensitive device. Alternatively, steps (i) and (ii) can be reversed.

• la figure 1 représente schématiquement sous forme de blocs fonctionnels un système de charge connecté via une ligne pilote et une prise de connexion électrique à un réseau de distribution électrique selon un mode de réalisation de l'invention.

Other features and advantages of the present invention will appear more clearly on reading the following detailed description of embodiments of the invention given as non-limiting examples and illustrated by the appended drawing, in which:

• the figure 1 schematically shows in the form of functional blocks a charging system connected via a pilot line and an electrical connection socket to an electrical distribution network according to one embodiment of the invention.

As is visible on the figure 1 , the electric or hybrid vehicle, corresponding to the part denoted VE or VH, is connected to an electricity distribution network via a pilot line 2 and an electrical connection socket 4. The connection socket is grounded 6 to level of the reload point.

Consider first the electrical connection socket 4. It comprises a temperature sensitive device 8 can be made for example by means of a thermistor, as shown, or a bimetal optionally in series with a resistor. The socket may also comprise a capacitor or equivalent device mounted in shunt and / or in series with the temperature sensitive device 8 for the purpose of protection against transient disturbances.

Then consider the pilot line 2 connecting the electrical connection socket 4 to a charging system 10 of the electric vehicle or hybrid (VE or VH). The pilot line 2 serves as a means of transmission between the charging system 10 and the electricity distribution network. This pilot line comprises a ground wire 2a connecting the ground 6 to one end of the temperature-sensitive device and to a reference potential of the vehicle and at least one wire 2b called "pilot", connecting the other end of the sensitive device to the temperature at the vehicle. The pilot wire 2b is connected to the recharging system to enable communication with the temperature-sensitive device, while in mode 3 it would allow communication with the point of recharging connected to the electricity distribution network.

Consider now the charging system 10 of the battery or batteries of the electric or hybrid vehicle. In input of the charging system is provided a charging connector 12 for connecting the pilot line 2 and the electrical connection socket. The charging connector 12 is an AC connector allowing, in mode 1, to connect it to a domestic network delivering an alternating current. It should be noted in passing that the mass of the charging system is equipotential with the earth, via the earth wire 2a.

It is preferably provided to provide the ESD electrostatic discharge protection means 14, for example, shunted and / or in series on the pilot wire 2b. The pilot wire 2b can also attack the charging system 10 of the vehicle via a capacitor 16 or an equivalent device connected in series and / or in series with the ESD protection means 14 (as shown). and against transient disturbances.

It is also intended to provide the charging system 10 of a circuit called pilot circuit 18. This pilot circuit comprises a diode D, resistors R2 and R3, and a switch S2. Their connection modes are defined by IEC 61851-1: 2010. The purpose of this pilot circuit is to confirm the connection of the vehicle to the recharging point on an electricity distribution network, to continuously confirm the integrity of a protective earth connection, to excite or de-energize the earth system. load and select a charge rate so as to provide the additional functions required for a different charging mode (ie mode 3) than the domestic charging mode or mode 1 defined in the draft standard aroused.

The pilot wire 2b can then attack processing means comprising for example a low-pass filter whose output is connected with an analog-digital converter (ADC), the output of which is itself connected to a processing unit (UT). The processing unit may be, for example, a microcontroller, a microprocessor, an erasable programmable logic circuit (EPLD) or a combination of several of these electronic components and / or equivalent components. The digital analog converter can be integrated in the processing unit, for example in the case of a microcontroller. The processing unit provides logical information of the boolean variable type (denoted "mode 1"), indicating, when it is true, that the current recharging is performed by direct connection to a socket of a local home network, as defined by IEC 61851-1: 2010. Finally, the charging system comprises polarization means preferably comprising a polarization source SP in series with a polarization resistor RP. These polarization means are implemented by a switch C actuated via the Boolean "mode 1" information. The polarization means have the function of biasing the temperature sensitive device 8 to a predetermined voltage by the polarization source SP via the resistor RP, this only when said "mode 1" Boolean information is true. The The polarization source is advantageously a source of negative voltage, for example -12V relative to the ground.

We will now explain the operation of the charging system according to the embodiment shown in FIG. figure 1 .

When the charging of the vehicle by a distribution network is not done in domestic mode or mode 1 according to IEC 61851-1: 2010, the signal mode 1 controls the switch C so that it remains open, so that the means polarization remain without effect.

Alternatively, when reloading is done in domestic mode or mode 1 according to IEC 61851-1: 2010, the signal mode 1 commands the switch C to be closed. As a result, the temperature sensitive device is biased by the voltage source SP via the resistor RP. Following this polarization, a value representative of the temperature of the device sensitive to the polarized temperature and therefore the temperature of the connection socket can be determined by a processing unit, preferably the same as that used for determining the charging mode. . This representative value of the temperature can be determined by any appropriate method, including using an algorithm and possibly a specific appropriate software (s), possibly using, as shown, the same low-pass filter and the same analog converter only for the analysis of the pilot line in mode 3.

Finally, it will be noted that the use of a negative polarization source SP of the temperature sensitive device makes it possible to prevent the pilot circuit, in particular the components D, R3 and possibly R2, from disturbing the temperature measurement of electrical connection because the diode D blocks most of the current flow when the pilot wire voltage is negative.

It will be understood that various modifications and / or improvements obvious to those skilled in the art can be made to different Embodiments of the invention described in the present description without departing from the scope of the invention defined by the appended claims.

Claims (10)

1. System for charging (10) an electric or hybrid vehicle including an AC charging connector (12) that is connectable to a domestic power-distribution network via an electrical-connection outlet (4) having a temperature-sensitive device (8), and a processing means (20, CAN, UT) for determining whether or not to use a charging mode 1 such as defined in the standard IEC 61851-1:2010, characterised in that the system for charging further comprises means for polarising (SP, RP) the temperature-sensitive device, activated when the charging mode 1 is used and means for determining (24) a value representing the temperature of the electrical-connection outlet by means of the polarised temperature-sensitive device.
2. System for charging (10) according to claim 1, characterised in that the charging connector (12) and the electrical-connection outlet (4) are connected by means of transmission comprising a ground wire (2a) and at least one pilot wire (2b) forming a pilot line (2).
3. System for charging (10) according to claim 2, characterised in that it further comprises a pilot circuit (18) connected to the pilot line (2) in order to ensure the compatibility of the system for charging with charging modes other than the mode 1.
4. System for charging (10) according to one of claims 1 to 3, characterised in that the means for polarising include a source of polarisation (SP) in series with a polarisation resistance (RP).
5. System for charging (10) according to claim 3 and 4, wherein the pilot circuit (18) comprises means for blocking (D) the passage of the current, and characterised in that the source of polarisation (SP) is a source of negative polarisation that activates the means of blocking of the pilot circuit.
6. System for charging (10) according to claim 4 or 5, characterised in that the activation means for polarising (SP, RP) is carried out by a switch (C) arranged on the polarisation circuit of the pilot line by the putting into series of the polarisation source and resistance.
7. System for charging (10) according to one of claims 1 to 6, characterised in that the means for determining (UT) a value representing the temperature of the electrical connection outlet and the processing means (20, CAN, UT) for determining whether or not to use a charging mode 1 share the same processing unit (UT).
8. System for charging (10) according to one of claims 1 to 7, characterised in that it comprises means for cutting off the charge activated when the determined value representing the temperature of the electrical-connection outlet (4) is greater than a predetermined threshold.
9. Electric or hybrid vehicle comprising a system for charging (10) according to one of claims 1 to 8.
10. Method for charging an electric or hybrid vehicle according to claim 9, connected to a domestic network for the distribution of electricity via an electrical-connection outlet (4) having a temperature-sensitive device (8), characterised in that it comprises the steps consisting in:

    - detecting the AC charging connector (12) in a distribution network of electricity;

    - determining whether or not to use a charging mode 1;

    - polarising the temperature-sensitive device (8) of the electrical connection outlet when the charging mode used is the charging mode 1; and

    - determining a value that represents the temperature of the electrical connection outlet by means of the polarised temperature-sensitive device.

Images